Onyx is a semi-precious form of
chalcedony, composed of fine intergrowths of quartz and moganite. Onyx is
formed from quartz and can be found in quartz deposits all over the world from
the US to Brazil to Madagascar.
Onyx has a smooth and slightly porous
surface. Onyx is also softer and a little more pliable than other natural
stone; this is due to a fairly low density compared to other harder natural
stones, such as granite.
Onyx has beautiful colors and patterns.
There are bold colors, including red, green, gold and blue; and soft colors
including gold, tan, brown, cream and sand.